Surgical Resection for Multifocal (T4) Non-Small Cell Lung Cancer: Is the T4 Designation Valid?

Background The current international staging system for lung cancer designates intralobar satellites as T4 disease. In this study, we sought to determine the impact of multifocal, intralobar non-small cell lung cancer (NSCLC) on patient survival and its potential relevance to stage designation. Methods We conducted a retrospective review of our thoracic surgical cancer registry from 1990 to 2005. Included were 53 patients with a resected lung cancer containing intralobar satellites detected preoperatively (n = 8) or in the resected specimen (n = 45). Patients with multicentric bronchioloalveolar cancer were excluded. All patients had an anatomic resection with mediastinal lymph node dissection. Median follow-up for the entire group was 31 months. Survival was calculated by the Kaplan-Meier method. A Cox proportional hazards regression model was performed to examine simultaneously the effects on overall survival of age, gender, nodal disease, number of satellite lesions, lymphatic invasion, and T status. Results The median age of the 53 patients with multifocal, intralobar (T4) disease was 68 years and 31 were women. Ten patients had more than one satellite lesion. Overall 5-year survival was 47.6% (95% confidence interval [CI], 27.36% to 65.30%) for all patients with resected intralobar satellites. Patients without nodal metastases had a 5-year survival of 58.4% (95% CI, 28.76% to 79.30%). The Cox regression identified female gender (adjusted hazard ratio [HR], 0.31; 95% CI, 0.10 to 0.96; p < 0.04) as a significant prognostic variable but only a trend towards significance for nodal status (adjusted HR, 2.3; 95% CI, .83 to 6.26; p < 0.11). Conclusions Patients with intralobar multifocal NSCLC detected in the resected specimen have a more favorable prognosis after surgical resection than might be predicted by their stage T4 designation. Five-year survival rates, especially in T4N0 patients, more closely approximate those with stages IB or II NSCLC.